I know many successful people who are not into drugs or even drinking for that matter who go to watch the concerts. While there may be some bad apples, many normal people enjoy the type of music played at these events.

It is all about having a good time. Here is a short video from a very similar (yet much larger) event to give you an idea of what goes on at these. http://youtu.be/cUhPA5qIxDQ